1. Field of the Invention
The present invention relates to a mobile terminal device configured to be connected to a network, and relates to a control method for connecting such a terminal device to the network.
2. Description of the Related Art
In recent years, a mobile terminal device such as an electronic still camera (hereinafter referred to as a digital camera) with a wireless communication interface to be wirelessly connected to a network such as LAN, etc., mounted thereon has become widely used.
A first object of mounting a wireless communication interface is to achieve data transfer without a wire.
Further, in recent years, a public wireless LAN service (called a hot spot, etc.) has been in the process of being prepared. Thus, transferring data of an acquired image to a server, etc., on the Internet from a place of visit via the foregoing LAN service by mounting the wireless communication interface on a portable terminal device itself such as a digital camera has been realized. This is a second object of mounting the wireless communication interface.
A third object is to connect the digital camera to a home (household electrical appliance) network through the wireless communication interface mounted on the mobile terminal device such as a digital camera. Thereby, the mobile terminal device becomes able to access image data stored in the digital camera without having to operate the digital camera from a personal computer (PC) or a television receiver, etc., connected to the network and becomes convenient.
However, an existing digital camera with the wireless communication interface mounted thereon has to issue a start instruction by means of a switch on the side of the digital camera in order to start an operation of the wireless communication interface and this causes a user inconvenience.
To solve the problem of the start by means of the switch, an always-on wireless communication interface is a possible approach. However, since wireless communication consumes a large volume of power even in reception, the always-on wireless communication interface poses a problem that a battery dies at short times. Even where constant connection to the network is enabled and PCs and television receivers connected to the networks are allowed to access the images stored in the digital camera, the above-mentioned short life of the battery becomes a problem.
Therefore, US 2006/0025105A1 has proposed a terminal device and a waiting operation control method which automatically starts a wireless waiting operation in addition to a start of supply of power form an external power source in order to solve the problem of power consumption and a troublesome operation of a start of waiting for wireless communication.